| Message ID | 4E47EB84.6080006@netcologne.de |
|---|---|
| State | New |
| Headers | show |
I wrote: > Hello world, > > the attached patch extends conversion warnings to assignments. > > OK for trunk? ... and forgot to say that this has been regression-tested. Thomas
Thomas Koenig wrote: > the attached patch extends conversion warnings to assignments. > OK for trunk? I get now two warnings for: complex(8), parameter :: z = cmplx (0.5, 0.5) r = z end Untested: Instead of checking if (rvalue->expr_type == EXPR_CONSTANT && (lvalue->ts.type == BT_REAL || lvalue->ts.type == BT_COMPLEX) && (rvalue->ts.type == BT_REAL || rvalue->ts.type == BT_COMPLEX)) one might check for: if (rvalue->expr_type == EXPR_CONSTANT && (lvalue->ts.type == BT_REAL || lvalue->ts.type == BT_COMPLEX) && (rvalue->ts.type ==rvalue->ts.type) Tobias
Am 14.08.2011 22:54, schrieb Tobias Burnus: > Thomas Koenig wrote: >> the attached patch extends conversion warnings to assignments. >> OK for trunk? > > I get now two warnings for: > > complex(8), parameter :: z = cmplx (0.5, 0.5) > r = z > end The problem is that gfc_check_assign is called twice for this, from different code paths: Breakpoint 1, gfc_check_assign (lvalue=0x7fffffffd8d0, rvalue=0x15bb020, conform=1) at ../../trunk/gcc/fortran/expr.c:3045 3045 { (gdb) bt #0 gfc_check_assign (lvalue=0x7fffffffd8d0, rvalue=0x15bb020, conform=1) at ../../trunk/gcc/fortran/expr.c:3045 #1 0x00000000004f70bb in gfc_check_assign_symbol (sym=0x15bb680, rvalue=0x15bb020) at ../../trunk/gcc/fortran/expr.c:3649 #2 0x00000000004e0670 in add_init_expr_to_sym (name=Unhandled dwarf expression opcode 0xf3 ) at ../../trunk/gcc/fortran/decl.c:1346 #3 0x00000000004e87d0 in variable_decl (elem=<value optimized out>) at ../../trunk/gcc/fortran/decl.c:2047 #4 gfc_match_data_decl (elem=<value optimized out>) at ../../trunk/gcc/fortran/decl.c:4124 #5 0x000000000052cb8a in match_word (subr=Unhandled dwarf expression opcode 0xf3 ) at ../../trunk/gcc/fortran/parse.c:65 #6 0x000000000052d3a0 in decode_statement () at ../../trunk/gcc/fortran/parse.c:283 #7 decode_statement () at ../../trunk/gcc/fortran/parse.c:232 #8 0x000000000052ea05 in next_free () at ../../trunk/gcc/fortran/parse.c:731 #9 next_statement () at ../../trunk/gcc/fortran/parse.c:923 #10 0x00000000005320de in gfc_parse_file () at ../../trunk/gcc/fortran/parse.c:4382 #11 0x000000000056b486 in gfc_be_parse_file () at ../../trunk/gcc/fortran/f95-lang.c:250 #12 0x00000000008fa978 in compile_file () at ../../trunk/gcc/toplev.c:548 #13 do_compile () at ../../trunk/gcc/toplev.c:1886 #14 toplev_main () at ../../trunk/gcc/toplev.c:1962 #15 0x00007ffff6f8aa7d in __libc_start_main () from /lib64/libc.so.6 #16 0x00000000004cade9 in _start () at ../sysdeps/x86_64/elf/start.S:113 (gdb) c Continuing. Breakpoint 1, gfc_check_assign (lvalue=0x7fffffffd9e0, rvalue=0x15bb020, conform=1) at ../../trunk/gcc/fortran/expr.c:3045 3045 { (gdb) bt #0 gfc_check_assign (lvalue=0x7fffffffd9e0, rvalue=0x15bb020, conform=1) at ../../trunk/gcc/fortran/expr.c:3045 #1 0x00000000004f70bb in gfc_check_assign_symbol (sym=0x15bb680, rvalue=0x15bb020) at ../../trunk/gcc/fortran/expr.c:3649 #2 0x000000000055a697 in traverse_ns (st=Unhandled dwarf expression opcode 0xf3 ) at ../../trunk/gcc/fortran/symbol.c:3333 #3 0x000000000055fd8c in gfc_traverse_ns (ns=0x15ba590, func=0x548200 <resolve_values(gfc_symbol*)>) at ../../trunk/gcc/fortran/symbol.c:3349 #4 0x00000000005475e1 in resolve_types (ns=0x15ba590) at ../../trunk/gcc/fortran/resolve.c:13511 #5 0x000000000053c4e4 in gfc_resolve (ns=0x15ba590) at ../../trunk/gcc/fortran/resolve.c:13593 #6 gfc_resolve (ns=0x15ba590) at ../../trunk/gcc/fortran/resolve.c:13581 #7 0x00000000005325cb in resolve_all_program_units (gfc_global_ns_list=<value optimized out>) at ../../trunk/gcc/fortran/parse.c:4247 #8 gfc_parse_file (gfc_global_ns_list=<value optimized out>) at ../../trunk/gcc/fortran/parse.c:4513 #9 0x000000000056b486 in gfc_be_parse_file () at ../../trunk/gcc/fortran/f95-lang.c:250 #10 0x00000000008fa978 in compile_file () at ../../trunk/gcc/toplev.c:548 #11 do_compile () at ../../trunk/gcc/toplev.c:1886 #12 toplev_main () at ../../trunk/gcc/toplev.c:1962 #13 0x00007ffff6f8aa7d in __libc_start_main () from /lib64/libc.so.6 #14 0x00000000004cade9 in _start () at ../sysdeps/x86_64/elf/start.S:113 What's the best way here? Add an "already checked" flag? I don't want to disable the test for complex.
On 08/15/2011 07:49 PM, Thomas Koenig wrote: > Am 14.08.2011 22:54, schrieb Tobias Burnus: >> Thomas Koenig wrote: >>> the attached patch extends conversion warnings to assignments. >>> OK for trunk? >> >> I get now two warnings for: >> >> complex(8), parameter :: z = cmplx (0.5, 0.5) >> r = z >> end > > The problem is that gfc_check_assign is called twice for this, from > different code paths Well, I don't think that this is the problem - the actual warning comes from the calling of the same code path: a) Call to gfc_check_assign_symbol from add_init_expr_to_sym: This does not print a warning for "z = cmplx(0.5,0.5)" (Side note: There is a conversion from kind=4 to kind=8) b) Call from gfc_resolve for "r = z" b.1) gfc_warning call in gfc_check_assign at expr.c:3228 -- the code which you added b.2) gfc_warning_now call in gfc_convert_type_warn (intrinsic.c:4349), which is called from gfc_check_assign (line 3272). (b.2) is guarded by else if (from_ts.type == ts->type || (from_ts.type == BT_INTEGER && ts->type == BT_REAL) || (from_ts.type == BT_INTEGER && ts->type == BT_COMPLEX) || (from_ts.type == BT_REAL && ts->type == BT_COMPLEX)) while (b.1) uses if (rvalue->expr_type == EXPR_CONSTANT && (lvalue->ts.type == BT_REAL || lvalue->ts.type == BT_COMPLEX) && (rvalue->ts.type == BT_REAL || rvalue->ts.type == BT_COMPLEX)) As written, you should consider changing this to, e.g., if (rvalue->expr_type == EXPR_CONSTANT && (lvalue->ts.type == BT_REAL || lvalue->ts.type == BT_COMPLEX) && (rvalue->ts.type == rvalue->ts.type)) or at least you should exclude rvalue == BT_COMPLX and lvalue == BT_REAL. Tobias
Index: fortran/expr.c =================================================================== --- fortran/expr.c (Revision 177746) +++ fortran/expr.c (Arbeitskopie) @@ -3190,6 +3190,53 @@ gfc_check_assign (gfc_expr *lvalue, gfc_expr *rval } } + /* If lvalue is REAL and rvalue is a REAL constant with different, + warn about possible errors the user may have done during conversion. */ + + if (rvalue->expr_type == EXPR_CONSTANT + && (lvalue->ts.type == BT_REAL || lvalue->ts.type == BT_COMPLEX) + && (rvalue->ts.type == BT_REAL || rvalue->ts.type == BT_COMPLEX)) + { + if (lvalue->ts.kind < rvalue->ts.kind && gfc_option.gfc_warn_conversion) + { + /* As a special bonus, don't warn about REAL rvalues which are not + changed by the conversion if -Wconversion is specified. */ + if (rvalue->ts.type == BT_REAL && mpfr_number_p (rvalue->value.real)) + { + /* Calculate the difference between the constant and the rounded + value and check it against zero. */ + mpfr_t rv, diff; + gfc_set_model_kind (lvalue->ts.kind); + mpfr_init (rv); + gfc_set_model_kind (rvalue->ts.kind); + mpfr_init (diff); + + mpfr_set (rv, rvalue->value.real, GFC_RND_MODE); + mpfr_sub (diff, rv, rvalue->value.real, GFC_RND_MODE); + + if (!mpfr_zero_p (diff)) + gfc_warning ("Change of value in conversion from " + " %s to %s at %L", gfc_typename (&rvalue->ts), + gfc_typename (&lvalue->ts), &rvalue->where); + + mpfr_clear (rv); + mpfr_clear (diff); + } + else + gfc_warning ("Possible change of value in conversion from %s " + "to %s at %L",gfc_typename (&rvalue->ts), + gfc_typename (&lvalue->ts), &rvalue->where); + + } + else if (gfc_option.warn_conversion_extra + && lvalue->ts.kind > rvalue->ts.kind) + { + gfc_warning ("Conversion from %s to %s at %L", + gfc_typename (&rvalue->ts), gfc_typename (&lvalue->ts), + &rvalue->where); + } + } + if (gfc_compare_types (&lvalue->ts, &rvalue->ts)) return SUCCESS; Index: testsuite/gfortran.dg/warn_conversion_2.f90 =================================================================== --- testsuite/gfortran.dg/warn_conversion_2.f90 (Revision 177746) +++ testsuite/gfortran.dg/warn_conversion_2.f90 (Arbeitskopie) @@ -7,5 +7,5 @@ x = 2.0 sqrt2 = sqrt(x) ! { dg-warning "Conversion" } - sqrt2 = sqrt(2.0) ! no warning; simplified to a constant and range checked + sqrt2 = sqrt(2.0) ! { dg-warning "Conversion" } end
Hello world, the attached patch extends conversion warnings to assignments. OK for trunk? Thomas 011-08-14 Thomas Koenig <tkoenig@gcc.gnu.org> PR fortran/46659 * expr.c (gfc_check_assign): Check for type conversions when the right-hand side is a constant REAL cor COMPLEX contstant the left-hand side is also REAL or COMPLEX. Don't warn when a narrowing conversion does not change the value of the constant. 2011-08-14 Thomas Koenig <tkoenig@gcc.gnu.org> PR fortran/46659 * gfortran.dg/warn_conversion_2.f90: Also warn about conversion of a constant resulting from simplification. * gfortran.dg/warn_conversion_3.f90: New test. ! { dg-do compile } ! { dg-options "-Wconversion -Wconversion-extra" } ! PR 47659 - warning about conversions on assignment ! Based on a test case by Thomas Henlich program main double precision d1, d2 real :: r1, r2 r1 = 2.3d0 ! { dg-warning "Change of value in conversion" } r2 = 2.5d0 ! No warning because the value does not change d1 = .13 ! { dg-warning "Conversion" } d2 = .13d0 end program main